"Such attacks are unacceptable and a swift and transparent investigation must be carried out to bring those responsible for this crime to justice," the European External Action Service said in a statement.
The European Union expressed its condolences to the family, friends and colleagues of the journalist.
"The European Union stands alongside the Ukrainian authorities in upholding the freedoms of expression and of the media, and will continue to work to protect journalists in their essential, professional work," the statement said.
Read alsoSheremet’s murder: Versions, eyewitness accounts, public reactionsPavel Sheremet, 44, a prominent Belarusian journalist who, had been working in Kyiv, was killed in a car bombing down town the Ukrainian capital on Wednesday.
